The Iceman Posted February 17, 2018 Author Share Posted February 17, 2018 Another thing is dews are currently in the teens. That is a very good thing. We LL see a solid temp drop when precip starts. That's a plus. Latest nam plus the hrrr both look solid still. I'm staying positive I really think this plays out better than most are expecting. Nws most likely map is still 3-6" for all of se pa last I checked. So while there are definitely things to be concerned about, I just still have a feeling about this storm. I've also been on board all week, feels wrong jumping ship now I'm calling the Philly special here... Link to comment Share on other sites More sharing options...
Rtd208 Posted February 17, 2018 Share Posted February 17, 2018 Temp has gone up pretty quickly here this morning, currently 35 here. Link to comment Share on other sites More sharing options...
The Iceman Posted February 17, 2018 Author Share Posted February 17, 2018 Very interesting disco from mt Holly posted below. I really trust their judgement when they say they don't see a blatant warm layer outside of s and e areas. Also say they are leaning on the nams thermals. Gorse is killing it this storm with the disco's. His thoughts are so clear and relays the difficulty of the forecast but I really like how he goes into depth of why they feel the way they do. Learned a few new things to look for in borderline events going forward. We really have one of the best nws offices in the world. I feel this one has a few surprises in store especially with the great forcing over our area. There will be some real good periods of near whiteout conditions. Quote other Nature looks to put on a show tonight as a quick moving storm affects our region. As mentioned in the near term section, a potent short wave will move across the Northeast tonight with height falls to its southeast. This will help sustain a surface low off the Mid- Atlantic coast as it quickly tracks northeastward and away from our area overnight. The model guidance overall is in good agreement with a widespread precipitation event occurring mainly through the first half of tonight. The large scale ascent will be augmented within a right entrance region of a potent 250 mb jet. In addition, lower to mid level frontogenetic forcing will enhance the precipitation especially through about 06z. Some of the high resolution guidance hints at some banding potential, however the quick movement of the system may result in any heavier embedded bands to be transient. Where this occurs is a tough call at this time, however somewhere in the I-95 corridor may be the zone where this may try and become more focused. It is here where the better transition takes place with the thermal fields, resulting in stronger forcing associated with frontogenetic mechanisms. It is within this enhanced forcing where snowfall rates of up to an inch per hour is very possible. The entire system and lift however are on the move with the associated lift moving out of the area after midnight. As a result, a 3-6 hour window of enhanced precipitation rates along with embedded heavier elements look to occur. The snowfall forecast is still challenging as the heavier rates will help overcome any lingering warmth close to the ground, although this is occurring at night. It is during the heavier snowfall rates where road conditions will deteriorate quickly especially where air temperatures hover right near freezing. The liquid to snow ratios will also be lower as one goes southeastward across our region. This will result in a zone of larger wet snowflakes especially during the time frame of enhanced lift where accumulations may end up being the most efficient. Given the extent of the dry air in place initially, wet bulbing should be a factor in allowing temperatures to drop a bit more. We therefore blended closer to the cooler guidance such as the NAM. The snow accumulations are mostly from the I-295/NJ Turnpike corridor westward, with amounts dropping off quite a bit to the south and east. The far southeastern areas and southern Delaware into portions of northeast Maryland should see little to no snow. The forecast soundings still look to not have a pronounced warm layer aloft, at least enough to produce much sleet therefore we did not factor this into the forecast all that much. Looks like rain, snow, rain/snow mix. Some mixing may get northwestward into Philadelphia before the precipitation ends. Given the forecast snow amounts and less confidence on where some banding may enhance local accumulations, we went with a Winter Weather Advisory for the Watch area and added a tier to the south and east. It is near and west of I-95 where the greatest snow accumulations are forecast, however the I-95 corridor needs to be monitored as a period of enhance lift, higher QPF and increased snowfall rates may result in a zone of higher amounts of wet snow. If 2-4 inches of wet snow falls and sticks efficiently in a short period of time, there could be some power outages. This potential impact is less certain. The storm quickly moves away overnight with precipitation ending quickly, and clouds should start to thin some from the west toward daybreak. Link to comment Share on other sites More sharing options...
The Iceman Posted February 17, 2018 Author Share Posted February 17, 2018 4 minutes ago, Rtd208 said: Temp has gone up pretty quickly here this morning, currently 35 here. Really our high temp doesn't have too much effect for tonight.. Dew points are more important to keep an eye on. As long as they stay in the teens or low 20s we LL be fine even if highs get a little above forecast. Link to comment Share on other sites More sharing options...
The Iceman Posted February 17, 2018 Author Share Posted February 17, 2018 33f/19f dp just before 10 am. My guess is we begin to see clouds roll in around noon time. I'd venture most of the area stays below 40 by then. Even with full sunshine right now it's not like temps are soaring at the moment. It feels warmer outside in the sun than it actually is in the air. Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 34 minutes ago, The Iceman said: Really our high temp doesn't have too much effect for tonight.. Dew points are more important to keep an eye on. As long as they stay in the teens or low 20s we LL be fine even if highs get a little above forecast. 20F DP here right now but damn it doesn't feel like snow out there. (bright sun and not cold in the sun) Birds chirping don't help...lol. Link to comment Share on other sites More sharing options...
JTA66 Posted February 17, 2018 Share Posted February 17, 2018 34F/19DP. Yeah, feels/looks like a spring day out there. If it wasn't for the mud, I'd get out and do a little yard work ...lol! I haven't had much enthusiasm for this event, maybe because whatever falls will be gone by tomorrow. But great job by Iceman staying on top of this one...bring it home for us! Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 Already 36F headed to 40...45 lol Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 20 minutes ago, JTA66 said: 34F/19DP. Yeah, feels/looks like a spring day out there. If it wasn't for the mud, I'd get out and do a little yard work ...lol! I haven't had much enthusiasm for this event, maybe because whatever falls will be gone by tomorrow. But great job by Iceman staying on top of this one...bring it home for us! Funny you said that. Landscaping crew cutting down a large tree down the road...like it's April/May without a worry in the world. Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 12z RGEM looks good a general 4-4.5" event. Paints a 7-8" bullseye just west of Kamu's squirrel country! Hrrr keeps loving the high counties but has gone up for the lower each run. Expectations set at 4" locally. Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 DP 22F / Temp 36F Link to comment Share on other sites More sharing options...
The Iceman Posted February 17, 2018 Author Share Posted February 17, 2018 Looking at goes 16.. looks like dc is just about to become overcast. With the fast movement of the clouds to the ne I would expect it to be over cast between 1 and 2 depends where you are. Temps will likely fall when that occurs and then crash again as precip rolls in with the dry air. Link to comment Share on other sites More sharing options...
ChescoWx Posted February 17, 2018 Share Posted February 17, 2018 34.7 here in East Nantmeal - hoping we can exceed last seasons snow total with tonight's event (need about 5")....would need about 7" to get us back up to normal seasonal snow through today's date. Latest WXSIM has us at 5" to 6" of snow by 1am...we shall see Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 22 minutes ago, Birds~69 said: DP 22F / Temp 36F DP 24F / Temp 37F Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 38.3F Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 This blows...40s here we come. Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 39.6F! Sunny skies how high will it go wheeeeee, never would have imagined near clear skies at noon with snow expected 5-6pm * 39.7 * 40.3 Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 42F Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 12z HREF still has 6-8" for all us in PA lol, this one is not backing off Link to comment Share on other sites More sharing options...
ChescoWx Posted February 17, 2018 Share Posted February 17, 2018 36.4 in East Nantmeal with DP 21 Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 This is a maddening hobby i keep checking at the Hrrr runs and every hour it paints a little more green in PA it now has the first couple hours as rain even in my neck of the woods Link to comment Share on other sites More sharing options...
penndotguy Posted February 17, 2018 Share Posted February 17, 2018 37 DP@20 with clouds increasing Link to comment Share on other sites More sharing options...
Birds~69 Posted February 17, 2018 Share Posted February 17, 2018 9 minutes ago, penndotguy said: 37 DP@20 with clouds increasing Yep, some high clouds moving in... Temp 41.4F / DP 26F Link to comment Share on other sites More sharing options...
Newman Posted February 17, 2018 Share Posted February 17, 2018 We're threading the needle in the middle of a torch period. I'll be glad to get any snow I can. Currently 36F, forecasted high is 37. Link to comment Share on other sites More sharing options...
Rtd208 Posted February 17, 2018 Share Posted February 17, 2018 Current temp is 37/DP 26 Link to comment Share on other sites More sharing options...
KamuSnow Posted February 17, 2018 Share Posted February 17, 2018 2 hours ago, RedSky said: 12z RGEM looks good a general 4-4.5" event. Paints a 7-8" bullseye just west of Kamu's squirrel country! Hrrr keeps loving the high counties but has gone up for the lower each run. Expectations set at 4" locally. I saw that, lol. Still lots of variation in modeled snowfall, tracking this event has been a little crazy. Should be interesting, hopefully in a good way for all of us. Going to blow some leaves in a few spots this afternoon, followed by a kettle fire. This will be a first, waiting down there by the fire for snow, checking radar. Lots of anticipation! Just starting to cloud up here now, temp at 41F, DP 25F. Hoping for cold air aloft to hang in there, not so worried about the surface. We've had a few events in the last few years here where we accumulated decent snow with the surface temp only getting down to 33F. Expectations here are 2" to 3", more would be a bonus. Could go either way, keeping fingers and toes crossed! Link to comment Share on other sites More sharing options...
Hurricane Agnes Posted February 17, 2018 Share Posted February 17, 2018 Temp here is 41F w/dp 25F. Starting to cloud up although looks like I'm getting some more stratusey low clouds. Going to a niece's birthday party tomorrow and am trying to decide whether to throw a cover over my windshield to reduce the SUV clean-off time tomorrow or let 'er ride and hope it all melts by noon. Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 40.1F clouds are here and it's about time Link to comment Share on other sites More sharing options...
RedSky Posted February 17, 2018 Share Posted February 17, 2018 Let's all calm down and have some coffee ECM keeps it's colder snow look for most of our region 4-6" and bumped up central and northern bucks into montco with a 6-8" 39.6F Link to comment Share on other sites More sharing options...
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